Steam boiler structure



March 14, 1933- J. E. MUHLFELD STEAM BOILER STRUCTURE Filed May 11, 1929 3 Sheets-Sheet l INVENTOR v @4924 ATTO% QM MN March 14, 1933. J. MLJHLFELD 1,901,465

STEAM BOILER STRUCTURE Filed May 11, 1929 s Sheets-Shet 2 INVENTOR fo/m Z. Mzz/glfeld M ATTORN Y March 14, 1933. MUHLFELD 1,901,465

STEAM BOILER STRUCTURE Filed My 11, 1929 3 Sheets-Sheet 3 INVENTOR W: ATTORN Patented Mar. 14, 1933 UNITED STATES JOHN E. MUHLFELD, 'OF' SGARSDALE, NEW YORK STEAM BOILER STRUCTURE Application filed May 11, 1929. j Serial No. 362,273.

vof juncture between the various angularly' 10 related parts of the structure being curved on a camparatively large radius whereby the necessity of lapping or welding or rlvetmg or the use of welt strips is avoided. I thus obtain a structure which is not only of the requisite mechanical strength, but which will be comparatively light in weight.

It is a more particular object of the invention to provide a steam boiler structure of the above character in which the upper and, lower steam and water drums are connected with the main boiler shell by front, intermediate and rear headers afiording communication at such points for the free circulation of the water and steam between the drums and the boiler shell, the spaced walls of each header being integrally joined and connected with the drums and the shell in the manner above stated, and the header walls acting in the nature of diaphragms permitting of expansion andcontraction of the walls of said boiler shellan'd the drums. With the'above and other objects in view, the'invention consists in'the improved steam boiler structure and in the form, construction and relative arrangement of its several parts as will be hereinafter more fully described, illustrated in the accompanying drawings, and'subsequent'ly incorporated in 40 the subjoined claims.

In the drawings, wherein I have illustrated one practical embodiment of the invention and "in' which similar reference characters designate "corresponding throughout the several .views,-

Figure 1 is a wide elevation of the unitary boiler structure; I Fig. 2 is a rear end elevation thereof; Fig.3 is a transverse sectional View taken .50 on the line 3- 3 of Fig. 'l;', I

extend forwardly "over the boiler Fig. 4 is a similar sectional on the'line of Fig. 1;; Fig. 5 is. an enlarged longitudinal section 1 al 7 view through the rear portion of the structure taken substantially on the lines 55 of Figs. 2 and 3,and s Fig.6 is a similar enlarged sectional viewthrough. the front portionof the structure taken substantially on'the' line" 6'.6 of Fig.4. '1. fi

In the accompanying drawings, I have selected for purposes of illustration, a boilerstructure designed for use in connection with high poweredlocomotives, which is generally similar to the fabricated boiler 5 structure shown and described in United States Letters Patent No. 1,611,770. It'fis i t en to be understood however, as this description proceeds, that the essential features ofthe present disclosure are likewise applicable to various other types of locomotives, marine or stationary industrial boilers.

In the construction shownin the drawings, the main boiler shell indicated at 5 may be of' any predetermined length and diameter., With this shell the upper steam drums .6 and the lower steam and water drums 7 located at opposite "sides foffthe central axial line of the shell are operatively associated. The upper steam drums-'6 are of greater length than the lower drums 7 and shell 5 as wellzasrearwardly therefrom. v 1 r v "The forward ends of theseup'per drums are integrally connected with the wall of the mainboiler shell 5' and communicate interiorly with said shell through themedium of a front header indicated at 8. This .headeris preferaby though not necessarily of the general cross sectional form se'en in Fig. 4 of the drawingsand jimmediatelybe low the drums 6jthe walls of said header merge into thetop and side walls of the shell 5.

The forward ends of the lowersteam'and I water drums 7 and also the upper steam drums 6 are likewisejintegrally connected with the rear end of the boiler shell 5Iand in communication with the latter through I the medium of an intermediate header 9.

The front wall of this header at its juncture with the walls of the drums and the shell 5 is connected therewith by the fillet wall sections of relatively large radius 5 shown at 10, and similar wall sections 11 also connect the rear wall of the header 5 integrally with the upper and lower drums 6 and 7. The forward ends of the upper drums 6 are in like manner integrally joined with the wall of the main boiler shell 5 by the large radius fillet walls 12.

The drums 6 and 7 at their rear ends'are connected with each other by the rear header 13, the front wall of which is integrally joined to the drum walls by the large radius fillet connections 14. [At the proper locatio n the spaced-walls of'this rear header are integrally joined with each other by thecontinuous transversely curved wall section 15' which bounds the elongated fire opening indicated at 16. At its upper and lower ends the rear wall of the header 13 provided with spaced manholes indicated at 17 and 18 in communication with the rear ends of the upper, and lower drums The boiler; shell 5 at a point spaced forwardly from the front'ends of the drums 6 is internally formed with the front end tube and flue sheet 21 whichis provided with the' openings 22 therethrough to receive the forward ends of the fire tubes and fines, the rear wall of the intermediate header 9' being similarly provided with the openings indicated at 23 to receive the rear ends J to the production of castingsofsteels and of said'tubes and flues. v

" Forwardly ofthe tube and flue sheet 21, the front end portion of the shell 5 constitutes the usual smoke box designated at 24 with thetop wall of which the outlet stack 25 for the smoke and gases is integrally formed. 5 Between this stack and the flue sheet 21, the top wall 'ofrthe smoke box is provided withan opening surrounded by afian'ged boss indicated at 26 upon which.

the superheater is mounted and suspended v within saidsmokebo'x;

, Eachfof the upper steam drums 6 adjacent jitsforward end is providedwitha "steam outlet surrounded by the flanged boss 27 to which suitable steamdome connections arel'adapted to be attached. Also the top a of the boiler shell 5 in advance of the drum 1 63$ provided with a steam outlet? opening.

' 28"for the safety valve connection,

'The spaced parallel wall sections of each of the headers 8, 9 and 13 are rigidly con nected in the usual manner by the stay bolts indicated at 29, 30 and 3lirespectively.

The space between the lower drums 7 and the upper drums 6 rearwardly of the boiler shall 5 defines the firebox chamber, and the drum walls are provided with the openings indicated at 32 in which the upper and lower ends of vertically extending water tubes (not shown) forming the opposite side be secured in accordance with the usual prac-' tice in the art. From the. foregoing description, the'several novel features of my new unitary steam boiler" structure and the advantages there- 'ofin' practical use will be readily understood. The production of this structure in the form of a one piece casting" not only greatly'expedites the manufacture of such boiler structures in comparison with "the time consumed in the production and assemblage of the numerous separateparts of the usual walls of the firebox chamber are adapted to fabricated boiler structure, but also material-Q.

ly reduces production costs by eliminating the use of a large number-of machines required in the proper formation of the fabricated parts, and the veryinaterial reduction of labor costs incident thereto.

By providing in sucha unitary structure, the large radius joint'connections between the walls of the vertical headers or waterlegs and the boiler shell" end drums, expan sion and contraction in the walls of the lat: ter is permitted without liability of the" formation of fractures in said joint connections. 'Thu's thenecessity of making frequent-repairs which ismore'or less common in fabricated boiler structures due to open-M "ing of the joints and leakage'caused' by the forces of expansion and contraction will be obviated. i i I i As a result of the progress which has been made in the metallurgical art with reference other "alloy 'metals, which have the same strength; per unit of section @as fabricated forged or rolled'plates heretofore used'in similar structures, it has been made possible to produce such a unitary one piece cast ing as-above described with assurance of the requisite strength and resistance to pressure strainsin all parts of thestructure.

I have herein shown and ,described an;

. embodiment of mypresentimprovements as applied to a particular typeof steam boiler structure, but in the numerous other boiler types employed fora great variety of differ-' ent purposes to which the essential features,

of the present disclosuremay be applicable,

it is possible that certain variations in'the V ilege of resorting to all such legitimate 7 changes therein as may be fairly embodied within the spirit and scope of the invention as claimed.

I claim: I

1. A unitary steam boiler structure comprising a boiler shell proper, upper and lower drums extending longitudinally of the boiler shell, and water and steam circulating conduits having their walls integrally formed with the walls of said boiler shell and the drums, and said integral connections consisting of joint forming wall sections curved on a comparatively large radius to permit of relative movement between the walls of the conduits and the walls of said drums and boiler shell. 1

2. A steam boiler structure comprising a one piece casting of a single metal composition including a boiler shell, longitudinally spaced water legs, and upper and lower drums integrally connected, and the walls of said boiler shell, the water legs and the drums being of substantially uniform thickness whereby the same ratio of contraction and expansion in all parts of said walls is obtained.

3. A boiler construction for locomotives,-

comprising a boiler shell proper, a drum communicating with said shell and extending therefrom, and a header interposed between the boiler shell and drum, and formed integrally with said boiler shell and drum, and said boiler shell and drum being joined to the header by curved wall sections flexibly yielding and of large curvature topermit relative movement between the wall portions of the boiler shell, drum and header during expansion of the same. a

4:. A boiler construction for locomotives, comprising a boiler shell proper, a drum communicating with saidshell and extending therefrom, and a header interposed between the boiler shell and drum and formed integrally with said boiler shell and drum, and of large curvature to permit relative movement between the wall portions of the boiler shell, drum and header during expansion of the same, said curved portions and the wall portions of the shell, drum and header there adjacent being of substantially uniform thickness.

In testimony that I claim the foregoing as my invention, I have signed my name hereto.

JOHN E. MUHLFELD. 

